Copyright Goodheart-Willcox Co., Inc.
164 Section 1 Preparing to Build
much earth must be removed to excavate a basement
or trench a foundation footing. Grade leveling is also
useful to determine how much earth must be depos-
ited in a particular area to achieve a desired height or
elevation at that location.
When the leveling instrument has been set level, the
line of sight will also be level. The readings can be used to
calculate the difference in elevation, Figure 8‑22. If the
building site has a large slope, the instrument may need
to be set up more than once between the points where
you want to take readings. The first reading is taken with
the rod in one position. Then, the instrument is carefully
rotated to get the reading at a second rod position. Of
course, if a laser level is being used, it will not be neces-
sary to rotate the instrument. Simply move the rod to the
second position and take that reading. This position may
be higher or lower than the first position.
Pro Tip
From a practical standpoint, it is simpler to work from a
higher point on the site than a lower point. Depending on
the actual slope, this measurement can often be made
with a single reading.
5uni2032-2uni2033
5uni2032-9uni2033
A
B
B
A
Goodheart-Willcox Publisher
Figure 8‑22. Establishing a grade level and finding the
difference between two points on a building lot. Top—Level
the instrument and take a line of sight reading on point A.
Mark down the rod reading. Bottom— If using a builder’s
level or transit, swing the telescope 180°, and take a line of
sight reading on the rod. Compare the two elevations. In this
example, point A is 7″ higher than point B.
The term grade means the level of the ground. Elevation
refers to the major structural levels of the building. More
specifically, these levels include the top of the footing, top
of the foundation wall, and finish height of the first floor.
There should be a reference point (level) for all ele-
vations established on the building site. This reference
point is called the benchmark, also known as the datum
or simply the beginning point. This point must remain
undisturbed during the construction of the building
project. A stake driven at one corner of the lot or build-
ing site, or even a mark chiseled into concrete curbing,
often serves as the benchmark.
P R O C E D U R E
Checking Grade
Building sites are rarely perfectly level. All have high and
low points. These highs and lows need to be determined
before the height of the foundation is established. This
job is easier when the site is fairly level, as in Figure 8‑22.
1. Locate the instrument midway into the site, then
level the instrument.
2. Take a line-of-sight reading on a rod held at one
edge of the site.
3. From the position of the target on the rod, note the
elevation (5′-2″ in Figure 8‑22) and record it.
4. Take a line-of-sight reading on the rod located at the
opposite side of the site.
5. Note the elevation at the target position on the rod
(5′-9″ in Figure 8‑22). Record it as before.
6. Subtract the lower elevation from the higher one to find
the difference (7″). This number is the actual vertical
increase or decrease from one known point to another.
When setting grade stakes for a footing or erecting
batter boards, set the instrument in a central location on
the site, as shown in Figure 8‑23. The distances to the
target (or rod) will be roughly equal. This will improve
the accuracy of the readings taken for each corner.
An elevation established at one corner can be quickly
transferred to other corners or points in between.
Pier
footing
Building line
Tripod
Goodheart-Willcox Publisher
Figure 8‑23. A central location for the instrument will make
finding and setting grade stakes easier and more accurate.
164 Section 1 Preparing to Build
much earth must be removed to excavate a basement
or trench a foundation footing. Grade leveling is also
useful to determine how much earth must be depos-
ited in a particular area to achieve a desired height or
elevation at that location.
When the leveling instrument has been set level, the
line of sight will also be level. The readings can be used to
calculate the difference in elevation, Figure 8‑22. If the
building site has a large slope, the instrument may need
to be set up more than once between the points where
you want to take readings. The first reading is taken with
the rod in one position. Then, the instrument is carefully
rotated to get the reading at a second rod position. Of
course, if a laser level is being used, it will not be neces-
sary to rotate the instrument. Simply move the rod to the
second position and take that reading. This position may
be higher or lower than the first position.
Pro Tip
From a practical standpoint, it is simpler to work from a
higher point on the site than a lower point. Depending on
the actual slope, this measurement can often be made
with a single reading.
5uni2032-2uni2033
5uni2032-9uni2033
A
B
B
A
Goodheart-Willcox Publisher
Figure 8‑22. Establishing a grade level and finding the
difference between two points on a building lot. Top—Level
the instrument and take a line of sight reading on point A.
Mark down the rod reading. Bottom— If using a builder’s
level or transit, swing the telescope 180°, and take a line of
sight reading on the rod. Compare the two elevations. In this
example, point A is 7″ higher than point B.
The term grade means the level of the ground. Elevation
refers to the major structural levels of the building. More
specifically, these levels include the top of the footing, top
of the foundation wall, and finish height of the first floor.
There should be a reference point (level) for all ele-
vations established on the building site. This reference
point is called the benchmark, also known as the datum
or simply the beginning point. This point must remain
undisturbed during the construction of the building
project. A stake driven at one corner of the lot or build-
ing site, or even a mark chiseled into concrete curbing,
often serves as the benchmark.
P R O C E D U R E
Checking Grade
Building sites are rarely perfectly level. All have high and
low points. These highs and lows need to be determined
before the height of the foundation is established. This
job is easier when the site is fairly level, as in Figure 8‑22.
1. Locate the instrument midway into the site, then
level the instrument.
2. Take a line-of-sight reading on a rod held at one
edge of the site.
3. From the position of the target on the rod, note the
elevation (5′-2″ in Figure 8‑22) and record it.
4. Take a line-of-sight reading on the rod located at the
opposite side of the site.
5. Note the elevation at the target position on the rod
(5′-9″ in Figure 8‑22). Record it as before.
6. Subtract the lower elevation from the higher one to find
the difference (7″). This number is the actual vertical
increase or decrease from one known point to another.
When setting grade stakes for a footing or erecting
batter boards, set the instrument in a central location on
the site, as shown in Figure 8‑23. The distances to the
target (or rod) will be roughly equal. This will improve
the accuracy of the readings taken for each corner.
An elevation established at one corner can be quickly
transferred to other corners or points in between.
Pier
footing
Building line
Tripod
Goodheart-Willcox Publisher
Figure 8‑23. A central location for the instrument will make
finding and setting grade stakes easier and more accurate.